1. Field of the Invention
The present invention relates to hydraulically powered lifts for vehicles, and in particular for vehicle lifts that are used on a solid surface having a pit, the lift straddling the pit.
2. Description of the Prior Art
Vehicle and automotive repair establishments often must be able to raise the vehicle, such as a car, truck, etc. The vehicle must be raised to various levels depending upon the task to be performed by the service personnel. In many applications, such as vehicle body repair, tire rotation, front end alignment, brake servicing, as well as new and used vehicle preparation and reconditioning, the desired height may be limited, thus necessitating the use of a "low-rise" surface mounted lift as distinguished from below ground buried lifting cylinders. Such low-rise lifts are typically bolted to the surface of the floor of a service bay in a garage, and some can be mounted on wheels for mobility.
The problem with many of these prior art low-rise lifts is that they are not made to fit newer garages designed to have a pit. In many new vehicle repair and service establishments, a working surface such as a concrete surface is placed above an open space or pit that it typically 2.5 to 3 feet in width and several feet in length. Service personnel can then go into the pit and service a vehicle driven and parked over the pit, the two wheels on either side of the vehicle straddling the pit.
In most garages with pits, the pit is lined on its upper edge adjoining the working surface with a rail. rail is typically "L" shaped in cross-section, having one edge (or afoot safety guard) extending and rising from the working surface from 2-4 inches, and the other edge forming a holding surface for such implements as an oil pan. This rising edge of the rail creates a discontinuity in the working surface of the garage wherein presently used low-rise lifts will not operate properly. The use of a low-rise lift under such circumstances necessitates, at a minimum, having to cut the rail edge that rises from the surface. Since the rail is typically hardened steel or iron, this is difficult and time consuming as well as unsafe.
Further, most low-rise lifts have cross-members joining the two lift platforms, the cross members further hampering its use over a pit where access from below the vehicle in the pit is partially blocked. This can also create a safety problem for the workers below who can injure themselves by hitting their heads on a stationary cross member. Also, the prior art cross-members were not adjustable to accommodate pits or vehicles of various widths. Since most low-rise lifts to date are not made for use in a pit, there is a need for an improved lift for such use. The lifts that do not employ cross members joining the two spaced apart platforms are unsafe and unreliable. As the lift wears, the two sides begin to lift independently at different rates since no cross member is present to join the sides. The vehicle being lifted is lifted at an angle which could result in the vehicle falling off the lift. The lack of a cross member decreases cross lead stability.